SBC: well-defined osteolytic lesion without expansion of the proximal meta-diaphysis of the humerus with pathologic fracture

Solitary Bone Cyst
-Solitary bone cyst, also known as unicameral bone cyst, is a true cyst.
- Many well-defined osteolytic lesions are often called cystic, but this is a misnomer.
-SBC frequently presents with a fracture. Sometimes a fallen fragment is appreciated. Predilection sites: proximal humerus and femur.
-Usually less expansion compared with ABC.
-Differential diagnosis: ABC, FD when cystic. SBC may migrate from metaphysis to diaphysis during growth of the bone.
-Discriminators:
Must be under age 30.
Must be centric


http://www.radiologyassistant.nl/en/4bc6176e56228

simple bone cyst

Location:Metaphyseal,central.

Age:Children(6-10).

Pattern of bone destruction:Geographic type 1 b-lytic lesion

D.D. according to location and age

-Fibrous dysplasia.

-Pyogenic osteomyelitis.

-Enchondroma

-Simple bone cyst.

Discussion:The pattern of bone destruction (geographic) can exclude pyogenic osteomyelitis,while appearance as a lytic lesion could exclude enchondroma due to abscense of chondral matrix,also abscense of internal septation could exclude fibrous dysplasia.

Diagnosis:Simple bone cyst.